The cultivation of agricultural crops has evolved over the years as the size and scale of farms has increased from small family farms to large-scale farms. Irrespective of a farm's size, variations in terrain, soil conditions and weather exposure produce non-uniformities of field conditions which affect the preparation and growing of crops.
In order to optimize crop yields, farmers have historically kept track of rainfall, humidity and temperature, as well as soil conditions and the occurrence of bug infestations. More recently, soil has been analyzed to determine nitrogen levels and various other conditions. Even furthermore, advances have been made with the introduction of field condition sensing and data collection which enable gross categorization of agronomic information on a field being cultivated. However, further improvements are needed that will enable better collection and management of agronomic information so that yields can be increased, without overly increasing the costs of production.
Recently, in-ground moisture sensors have been combined with an irrigation controller to control an irrigation cycle of an area of soil. More particularly, such irrigation controllers have been used to control stationary irrigation devices such as are used in golf courses and in orchards. However, such systems are limited in that in-ground sensors tend to be costly and only monitor soil conditions immediately adjacent the sensor. Therefore, it is cost prohibitive to provide a large number of sensors in order to cover a large agricultural field being processed by a large-scale irrigation device such as a center-pivot irrigation device. Furthermore, such stationary irrigation systems are not suitable for irrigating large-scale agricultural fields due to the large number of sprinklers needed on the irrigation system. Furthermore, an agricultural field needs to be periodically cultivated and a complex in-ground irrigation system will cause problems when the field is being turned over is and prepared for its next cultivation cycle.
A typical large-scale farm employs a sprinkler irrigation system for applying water and chemicals to a crop which is being raised. One type of sprinkler system consists of a center-pivot irrigation device which is typically configured to apply water and chemicals to a circular plot of land. End features have been added to such devices in order to adapt them for irrigating square plots of land via the use of controllable end guns, or articulating end booms contained therealong. A typical center-pivot irrigation device has a fixed pivot, and a long body carried by an array of towers having support wheels. A plurality of sprinklers are fixed in spaced-apart relation along the arm, each sprinkler being activated by way of a solenoid valve which enables turning "on" and "off" of a sprinkler nozzle in order to regulate application of water and chemicals to the agricultural field. In operation, the long body, or arm, is rotated about the fixed pivot via the towers, as drive motors on each tower drive the support wheels, causing the device to rotate about the fixed pivot. One or more sprinklers are activated by way of a solenoid valve which distributes water at a desired rate. The rate of application typically depends on the radial location of each particular sprinkler, such that the final result produces a somewhat uniform distribution of water across the field.
Recently, attempts have been made to enable a variable-rate application of water and chemicals to a field in order to deliver water and chemicals to regions of the field in differing amounts. One such effort is disclosed in U.S. Pat. No. 5,246,164 to McCann, et al., entitled "Method and Apparatus for Variable Applications of Irrigation Water and Chemicals". According to this construction, a center-pivot irrigation device having a plurality of sprinkler assemblies arranged in a fixed array is operable to distribute an adjustable amount of water over a zone of ground as the arms pivot about the fixed point. However, further improvements are needed to enhance mobility and accuracy.
Other areas of recent improvement in the field of agriculture involve the use of precision agriculture products. Precision agriculture products typically utilize variable-rate application devices, global positioning system (GPS) devices, and geographic information systems (GIS). Satellite-based global positioning systems enable the determination of precise locations within a field of interest. Geographic information systems enable data management of detected conditions on a field of interest.
One presently available suitable differential global positioning system is manufactured by Trimble, and is sold under the product name Direct GPS for Arc View, Trimble Surveying and Mapping Division, 645 North Mary Avenue, P.O. Box 3642, Sunnyvale, Calif. 94088-3642.
One suitable geographic information system (GIS) is presently available from Environmental System Research Institute, Inc. (ESRI), 380 New York Street, Redlands, Calif. 92373-8100, under the name "ARCVIEW.RTM., for Agriculture". Such a GIS system enables the management of agricultural information by way of a graphical user interface. The GIS system consists of software loaded into memory and implemented on a computer, and forms a graphical user interface that easily enables a user to tabulate data and evaluate collected data for making decisions about a crop being cultivated.
The use of precision agriculture products has been coupled with far-distance data collection techniques for determining certain agronomic features on a field being studied. Satellite imaging techniques and aerial photography techniques have enabled the collection of large amounts of data in order to characterize agronomic information and features on large fields of interest. For example, thermal imaging cameras have been used to determine certain thermal characteristics that manifest themselves on a field being observed. However, such cameras produce a gray scale array of pixels having limited resolution, and further, only collect information periodically when weather conditions permit flight overhead. Such flight-based collection is performed a far distance above a field being monitored. In some circumstances, the presence of certain crop and soil conditions will manifest themselves in the form of a thermally detectable variation upon the land. Similar detection can be performed in the visible, infrared and ultraviolet ranges, enabling the determination of correlated features with such information.
However, the ability to collect agronomic information on a field of interest via far-distance detection techniques often-times has limited capabilities. For example, inclement weather conditions can prevent the collection of information by blocking the ability to detect agronomic features. For cases of satellites, even the presence of moderate cloud cover can disrupt detection of such information. During certain periods of a growing cycle for a crop, the detection of such information can be critical to successful harvesting, as well as to the implementation of remedial measures that must be taken in order to counteract the effects of a bug infestation or fungal attack on plants. Hence, an improved technique which enables the detection of such agronomic information during any time of day, and under any type of weather condition, is desired. Furthermore, a sensing device that enables the detection of an increased number of different agronomic features is also desired. Additionally, a detection device that does not harm crops during the detection process, yet enables the collection of agronomic information while crops are being grown, is also desirable.
Although precision agriculture products have recently enhanced the ability to increase crop yields, further improvements are needed to reduce the overall cost of such systems while improving the control and application of such systems. For example, improvements are needed to enhance feedback-control of such systems in order to better respond to detected needs within a field in applying water and/or chemicals to such a field based upon the detected needs. Furthermore, improvements are needed to verify that such application is producing the desired result, and the field is actually receiving the water and chemicals where they are intended to be delivered. Even furthermore, improvements are needed in the manner in which chemicals are delivered to such a field, particularly for chemicals which are applied in very minute quantities, with very high concentrations. Even furthermore, improvements are needed in the manner in which chemicals are delivered to such a field, particularly where the chemicals are extremely expensive. Yet even furthermore, improvements are needed to the sensing systems in order to reduce their overall cost, while enhancing their overall effectiveness.
In accordance with the present invention, improvements are made to an automatic irrigation system to implement closed-loop control of an irrigation cycle with a movable irrigation device, a detector for detecting moisture presence within an agricultural field, and a controller which compares the detected moisture level with a desired level and regulates fluid delivery by controllably actuating a valve or triggering a switch which controls the fluid nozzles in response to the feedback signal from the detector.
In accordance with another aspect of the present invention, an automatic irrigation system has a movable irrigation device with a fluid nozzle for supplying fluent agricultural material to the agricultural field, and a detector which is configured to detect the actual application of fluent agricultural material to the agricultural field. A controller, coupled with the detector, detects the actual delivery of fluent agricultural material from the fluid nozzle and compares it with the intended delivery of fluent agricultural material so as to determine the operability of the fluid nozzle.
In accordance with yet another aspect of the invention, a movable irrigation device utilizes in-ground moisture detectors in combination with movable sensors to determine irrigation needs within a field being surveyed. In accordance with even another aspect of the invention, an irrigation device has a primary fluid flow conduit for supplying a first fluid and a secondary fluid flow conduit for supplying a second fluid to an agricultural field being processed. A controller is used to control output of water and/or chemicals from each of the first and the second elongated fluid flow conduits of the irrigation device.
In accordance with yet even another aspect of the present invention, a chemical and water irrigation device includes a detector of chemical concentration present within soil of an agricultural field, and a controller which causes the irrigation device to apply chemicals to an agricultural field based upon the detected need.
It is therefore a primary objective of the present invention to provide closed-loop control of a movable irrigation device so that detected moisture levels might be met without any human intervention.
It is a further objective to provide a system for monitoring operation of an irrigation valve such that an irrigation device can determine whether or not an irrigation valve is actually applying a desired chemical and/or water to an area within a field.
It is a further objective to provide an apparatus having a movable irrigation device which supplies fluent agricultural material to an agriculture field in response to needs that are detected by an in-ground sensor and at least one movable sensor carried by the irrigation device.
It is a further objective to provide an irrigation system for effecting chemical and water delivery via separate delivery lines so as to enable proper delivery of chemicals which are highly concentrated, or are delivered in small or minute quantities.
It is a further objective to provide an apparatus for delivering chemicals to an agricultural field in response to a detector which detects the presence of chemical concentration within soil of the agricultural field.
Other objectives, features and advantages of the invention will become evident in light of the following detailed description considered in conjunction with the referenced drawings of preferred exemplary embodiments according to the present invention.